1. Field of the Invention
The present invention relates to an apparatus for searching data from a large-capacity file on the basis of pattern features for matching or correlating and/or to identify pattern data such as finger print, seal, constellation or the like pattern data.
2. Description of the Prior Art
In the field of the apparatus of the type mentioned above, there exists a great demand for reducing to a possible minimum the time taken for recognizing the feature of a pattern to be examined as well as the time required for searching the data corresponding to the recognized feature from the large-capacity file.
In a conventional method of matching or correlating a finger print, seal or signature or the like, the image or the like pattern of the object to be correlated is searched with the aid of a registered or estimated identification number or the like, wherein the searched or retrieved image is correlated with the image to be examined in one-to-one correspondence. Difficulty is encountered in the searching and correlation when data such as the identification number is not available. In connection with the correlation of the constellations, there is developed a method of sequentially checking the whole sky as to the presence of the constellation having the feature pattern corresponding to that of an input constellation to be examined (Refer to T. Tanabe et al's article "Identification of Fixed Stars by Stellar Image Data" of a lecture collection at second congress concerning the attitude control, published by The Institute of Space and Astronautical Science, Feb. 24, 1983). This method is also disadvantageous in that an enormous time is required for the processing.